The present application is directed to modes of control for a personal transporter utilizing an electrical power source.
Dynamically stabilized transporters refer to personal vehicles having a control system that actively maintains the stability of the transporter while the transporter is operating. The control system maintains the stability of the transporter by continuously sensing the orientation of the transporter, determining the corrective action to maintain stability, and commanding the wheel motors to make the corrective action. If the transporter loses the ability to maintain stability, such as through the failure of a component, the rider may experience discomfort at the sudden loss of balance. For some dynamically stabilized transporters, such as those described in U.S. Pat. No. 5,701,965, which may include a wheelchair for transporting a disabled individual down a flight of stairs, it is essential, for the safety of the operator, that the vehicle continue to operate indefinitely after detection of a failed component. For other dynamically stabilized transporters, however, the operator may readily be capable of safely dismounting from the transporter in case of component failure. It is desirable that control modes be provided for such vehicles from which the operator is capable of safely dismounting in case of mishap.
In accordance with preferred embodiments of the present invention, a system and method are provided for automatically decelerating a personal transporter of the kind that has a controller for controlling the motion of the transporter. The method has steps of detecting a fault condition, setting a goal value of the control variable, adjusting the control variable at a specified increment in the direction of the goal value, and repeating the prior steps until the control variable equals the goal value. In accordance with alternate embodiments of the invention, the goal value may be zero, the control variable may be transporter speed, and the fault condition may be an open motor winding or a closed brake switch.
In accordance with another aspect of the present invention, a method is provided that affords a user accelerated access to operation of a balancing personal transporter. The method has the steps of initializing a single-axis stabilizer, beginning initialization of a 3-axis stabilizer, alerting the rider that the transporter is ready for use, allowing operation of the transporter, completing initialization of the 3-axis stabilizer, and, finally, employing the 3-axis stabilizer for control of the balancing personal transporter.